Environmental group Greenpeace has urged EDF to sever the contractual links to Russian state-owned firm Rosatom.
Reports claim the contract with the Russian nuclear power giant includes a deal to source uranium.
Uranium is a common fuel used by nuclear power stations.
Veolia has also been accused of having heating and waste supply contracts and providing essential public services.
Both companies insist they are in line with international sanctions.
An EDF spokesperson: “EDF is complying with all the British and French Governments’ requirements regarding sanctions imposed on Russia. EDF has stopped all business development in Russia and taken the decision to suspend the activities of its representative office there.”
A Veolia spokesperson told ELN: “Veolia UK is a business entity with no legal, financial or operational ties with Veolia’s Russian affiliate. Veolia UK maintains continuous dialogue with the UK authorities and public bodies to ensure its full compliance with all applicable sanctions.
“Veolia Group provides absolutely no new funding for the operations of its affiliate in Russia and has stopped all new investment and all financial flows between the Veolia Group and its Russian subsidiary.
“Veolia utterly condemns war and violence in Ukraine. In full compliance with the current sanctions regime, Veolia Group is maintaining its responsibility to its employees and the communities it serves by continuing its essential public service operations in both Ukraine and Russia.”